tempfile and tempdir should fail test when deletion fails

[Marcono1234]

Please describe the feature you'd like to see including any solutions in mind if you have any
Currently tempfile and tempdir use the java.io.File methods which merely return a boolean, and kotest does not check the result whether the file or directory was actually deleted.

Expected
Kotest should (by default?) detect when a temporary file or directory could not be deleted and cause a test failure with a descriptive message stating which files could not be deleted (ideally also first attempting to delete all and accumulating exceptions).

This allows test authors to detect when the tested application does not properly close resources, and avoids temporary files from accumulating.

Ideally this would use java.nio.file.Files methods to give more insight to the user why deletion failed.

For reference, JUnit 5 causes a test failure when deletion fails, see TempDirectory.java.

[sksamuel]

Good suggestion. Added to master will be included in the 5.0 release.